Principal Financial Group announced Tuesday it has completed its previously announced acquisition of MetLife Afore S.A. de C.V., MetLife Inc.’s pension fund management business in Mexico, attaining full regulatory approval for the deal. The purchase and integration will position its Principal Afore as the fifth-largest retirement plan administrator in Mexico with more than 7 percent market share. After the purchase, Principal in Mexico will manage around 3.4 million individual accounts for retirement with $12.3 billion of assets under management. “Mexico is a growing and important market for Principal,” said Luis Valdes, president of Principal International, the global pension business of Principal Financial Group. “We are committed to making investments in countries with a robust middle class to bring more people the long-term retirement and investing solutions they need to achieve a more secure financial future.”